Antivibration Coil Spring with Asymmetric Guide Spacing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hand-guided power tools with coil spring antivibration elements have uniform stiffness in all directions, requiring multiple elements for different damping behaviors, and rubber elements with varying geometries are complex to implement effectively.
Innovation Solution
The coil spring is designed with different radial spacings relative to the guide in various directions, allowing for varying damping effects by altering the effective spring length and stiffness, and the guide's shape, such as an oval cross-section or spiral grooves, adjusts damping characteristics without additional components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple antivibration elements are arranged in different directions to achieve different damping behaviors, then the damping characteristics can be optimized, but the device complexity increases
Solution Approach 1:
The guide is designed with non-uniform radial spacing in different directions, creating different stiffness characteristics locally. The guide has a smaller radial spacing in one direction and a larger radial spacing in another direction, allowing a single antivibration element to provide different damping behaviors in different directions without requiring multiple elements.
Solution Approach 2:
The guide features an asymmetric cross-sectional shape with different radial spacings to the coil spring in different directions. This asymmetric geometry creates different effective spring lengths and stiffness values depending on the direction of vibration, enabling directional damping control with a single element rather than requiring symmetric multiple elements.
2Reliability
If rubber antivibration elements with different geometries are used to achieve different stiffness in different directions, then the damping action can be optimized, but the manufacturing complexity increases
Solution Approach 1:
Instead of using rubber elements with different complex geometries, the invention uses a single coil spring with a guide that has locally varied spacing. The guide's radial spacing is smaller in one direction and larger in another, creating the desired different stiffness characteristics through the guiding constraint rather than through complex element geometries.
Solution Approach 2:
The invention replaces the need for geometrically complex rubber elements with a simpler coil spring system constrained by a guide with non-uniform spacing. The damping characteristics are achieved through the mechanical constraint of the guide geometry rather than through the inherent geometric complexity of the vibration element itself.
3Strength
If the coil spring is constrained closer to its center in a specific direction, then the stiffness in that direction increases, but the effective spring length decreases
Solution Approach 1:
The guide is designed with non-uniform radial spacing, being closer to the coil spring center in one direction and farther in another direction. This creates different effective spring lengths locally, resulting in higher stiffness in the direction with smaller spacing and lower stiffness in the direction with larger spacing, without requiring uniform constraint throughout.
Solution Approach 2:
The asymmetric positioning of the guide relative to the coil spring creates different effective spring lengths in different directions. The guide is positioned closer to the spring center in the direction where higher stiffness is desired, and farther away in directions where lower stiffness is acceptable, optimizing the damping characteristics directionally.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration provides tailored damping properties to match the power tool's needs, enhancing vibration damping and guiding behavior, and can be adapted to existing tools by exchanging guides or springs, resulting in improved performance without additional components.
Implementation Method 1
the antivibration element comprises a coil spring
Implementation Method 2
different damping effects of the coil spring in the different directions
Data Source
AI summary
A hand-guided power tool has a drive motor and a tool in driving connection with the drive motor. At least one handle is provided for guiding the power tool in operation. At least one antivibration element functionally connects the at least one handle and the drive motor. The at least one antivibration element has a coil spring and a guide, wherein the coil spring has an end connected to the guide. The coil spring has a first radial spacing relative to the guide in a first radial direction and has a second radial spacing relative to the guide in a second radial direction, wherein the second spacing is smaller than the first spacing or is zero.